The present invention relates to a vehicle lift or ramp of the pantograph or parallelogram type.
Lifts of this type are known in which a pair of base frames resting on the floor are connected with parallel elevatable wheel guides through pairs of columns having their ends pivotally connected with the base frames and wheel guides, together with hydraulic jacks to raise and lower the structure.
Generally, the base frames and wheel guides are C-shaped in cross section, with the aim of nesting these parts to reduce height when the structure is lowered, and at the same time providing a housing space for the lifting jacks and associated parts when the structure is lowered.
Also generally the two wheel guides are connected by sturdy cross bars to prevent unequal lifting, resulting in the formation of a horizontal lifting platform at the tops of the pairs of columns.
A major objective of this invention is to eliminate the necessity for cross bars or other braces beween the vehicle wheel guides, so that the space between the wheel guides is entirely open and unobstracted, thereby greatly facilitating service operations on the elevated vehicle without impeding the worker's movements.
Another object of the invention is to provide a vehicle lift of the mentioned type which can be easily knocked down for storage and transportation.
Yet another object is to provide a vehicle lift having safety means to stop the descent of the device in the event of failure of the hydraulic system supplying the lifting jacks, and in case a foot of a worker is placed between relatively moving parts of the descending structure.
Another object of the invention is to provide means for controlling the trim of vehicle wheels in a correct way, namely, with the four wheels of the vehicle placed in a truly horizontal plane.
Other features and advantages of the invention will become apparent during the course of the following detailed description.